PTI DC20.1 PDF

Introduction

Over the past twenty years the use of post-tensioned flat slabs in building construction has dramatically increased. In the mid 1970's designers began to use banded tendons (see Fig.1) for flat slab design. The width of a typical band of tendons may be eight times the slab thickness and may contain between six and ten tendons. Thus, the anchors must be placed very close together. Banded tendons have become popular for their structural efficiency as well as their simplification of the construction sequence and reduction in labor costs. Previous studies [2,4] of banded tendon flat plate systems have investigated overall structural behavior but not possible anchorage zone behavior for typical closely spaced mono-strand anchors as required for banded tendons.